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DNA Helicase
Role of DNA Helicase
DNA is an ATP-driven motor protein. Its role is
to unwind the duplex DNA in order to provide
a single-stranded DNA for replication,
transcription, and recombination for instance.
Discovery
The first eukaryotic DNA helicase discovery was
in 1978 and found in the lily plant. Since then,
DNA helicases were discovered and isolated in
other bacteria, viruses, yeast, flies, and higher
eukaryotes
How it works?
DNA Helicases possess common sequence
motifs located in the interior of their primary
structure. These are thought to be specifically
involved in ATP binding, ATP hydrolysis and
translocation on the nucleic acid substrate.
Conformation of DNA helicase
• JMOL FIRST GLANCE DNA HELICASE
KEY DISEASES ASSOCIATED WITH DNA
HELICASE DYSFUNCTION
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Alzheimer’s Disease
Neurological diseases
Predisposition to cancer
Premature ageing
Skin abnormalities
Fun Fact
DNA Helicase in humans deforms at 40 C
DNA Helicase as a cause of human
disease
• UV sensitivity; skin cancers, neurological abnormalities,
XP phenotypes, dwarfism, mental retardation, retinal
and and skeletal abnormalities, brittle hair, mental
retardation, reduced stature, ichthyotic skin, unusual
facies, predisposition to many cancers: non-Hodgkin’s
lymphoma, leukemia; dwarfism, sun-induced
erythema, type II diabetes, narrow face/prominent
ears, male infertility, female sub-fertility, premature
aging features: cataracts, type II diabetes, osteoporosis,
atherosclerosis, graying and loss of hair; mesenchymal
tumors: sarcomas, melanoma, thyroid cancer
DNA Helicase Joke
If I were an enzyme I
would be DNA helicase
so I could unzip your
genes.